True, there will be still a gap between the two and quite possibly it might be the manufacturers themselves rather than the available technology that might keep that gap wider than it could be, to preserve the different market segments and keep the "prestige" of the DSLRs.

However, past certain point of IQ, FPS, AF performance, etc, for 95% of shooters it will make no sense to go for higher than required, particularly if there is a price advantage. The point is that this is a new market segment that's not directed at entry level and that consumers will have very high expectations of.

When I can get clean images @ ISO3200, have reliable AF on moving targets, no shutter lag and some manual controls on a mirrorless, I will not ever get a new DLSR. I reckon that point is 2-3 years away.